超高压下CsBr的结构与相变  

THE STRUCTURE AND PHASE TRANSITION FOR CsBr UNDER ULTRAHIGH PRESSURE

作　　者：王莉君[1] 陈良辰[1] 李凤英[1] 顾惠成[1] 周镭[1] 车荣钲[1] 

机构地区：[1]中国科学院物理研究所

出　　处：《高压物理学报》1998年第2期92-96,共5页Chinese Journal of High Pressure Physics

基　　金：国家自然科学基金

摘　　要：采用金刚石对顶压砧高压装置（ＤＡＣ）、同步辐射Ｘ光源和能散法，对ＣｓＢｒ粉末样品进行了原位高压Ｘ光衍射实验，最高压力达１１５ＧＰａ。观测到在５３ＧＰａ左右压力下，ＣｓＢｒ的最强衍射峰（１１０）劈裂成两个峰，标志了简单立方结构向四方结构的转变；在０至最高压力范围内（相应于Ｖ／Ｖ０为１至０．４６３）测量了晶轴比ｃ／ａ；在１１５ＧＰａ内未观测到样品的金属化现象。In situ energy dispersive X ray diffraction measurements on CsBr under pressure up to 115 GPa have been performed by using pressure device—diamond anvil cell (DAC) with synchrotron source.It is determined that the structure of CsBr is changed from simple cubic phase to tetragonal phase at about 53GPa marked by the splitting of its strongest diffraction line (110) into two parts:(011) and (110).The lattice parameter ratio c/a has been measured from p =0 to the maximum pressure (corresponds to V/V 0 range of 1～0.463).No pressure induced metallization transition has been observed at higher pressure up to 115GPa.

关 键 词：CsBr 高压X射线衍射 超高压 结构 相变 

分 类 号：O521.2[理学—高压高温物理]